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4194A, B, and C Series
4. Decrease the remote set point pressure to 0 psig.
5. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Replacing the Remote Set Point Tubing
1. Decrease the remote set point pressure to 0 psig.
2. Using two 5/16-inch open-end wrenches, discon-
nect the pressure connection union (key 93) from the
pedestal assembly (key 105) and the connection to the
case exterior at the top of the case.
3. Remove the tubing (key 104).
4. Install the replacement tubing, and reconnect the
two pressure connections.
5. Apply full remote set point pressure, and check for
leaks.
Replacing Link A
This procedure describes link A (key 116) replacement
in the input portion of the remote set point assembly.
Figure 5-20 shows the link location.
1. Note the holes where link A is connected. Discon-
nect link A (key 116) from the lever arms on pivot as-
sembly A and pivot assembly B.
2. Loosen the screw in the replacement link A and
adjust the length to match the link being replaced.
Tighten the screw.
3. Refer to figure 5-20 for the correct link orientation.
Attach replacement link A to the two lever arms in the
same holes noted in step 1.
4. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Replacing Link B
This procedure describes the link B (key 126) replace-
ment of the remote set point assembly. Figure 5-20
shows the link location.
1. Note the holes where link B is connected. Discon-
nect link B (key 126) from the pivot arm and from the
set point indicator.
2. Loosen the screw in the replacement link B and
adjust the length to match the link being replaced.
Tighten the screw.
3. Refer to figure 5-20 for the correct orientation of
link B. Attach replacement link B to the pivot arm and
5–28
to the set point indicator in the same position as noted
in step 1.
4. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Remote Set Point (suffix letter M)
Maintenance Calibration
Refer to figure 5-20 for parts and adjustment locations.
Refer to figure 5-26 for key number locations.
Precalibration Procedures
1. Remove the two screws (key 6) and lift off the pro-
portional band indicator cover (key 36).
2. Set the proportional band between DIRECT and
REVERSE.
3. Remove the two screws (key 103) and remove the
tie bar (key 106) from the remote set point assembly.
Aligning the Flexures
1. Apply remote set point pressure input equal to 50
percent of the remote set point input range.
2. The guide flexure (key 119) should be straight and
horizontal. If not, straighten the flexure by loosening
the machine screw (key 122) on the end of the flexure
that is attached to the top of pivot assembly A (key
114) and allow the flexure to straighten itself. Tighten
the machine screw.
3. If the flexure is not horizontal, loosen the two ma-
chine screws (key 139) and raise or lower the pedestal
assembly (key 105) until the guide flexure is horizon-
tal. Retighten the machine screws (key 139) and en-
sure the diaphragm assembly extension (key 134) is
centered in the upper travel stop (key 83) hole.
4. The drive flexure (key 79) should be straight. If not,
proceed as follows:
a. Loosen the screw (key 118) on the adjustment
arm of pivot assembly A (key 114) and loosen the
screws holding the drive flexure.
b. Set the length of the adjustment arm so that the
drive flexure is parallel to the centerline of the dia-
phragm capsule assembly (key 80).
c. Tighten the screw (key 118) on the adjustment
arm.
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